Secondary electric batteries



p 1962 H. FRANKMANN I 3,052,745

SECONDARY ELECTRIC BATTERIES Filed'Sept. 21, 1959 2 Sheets-Sheet 1 Inven'for b Hans FranKmann H A'l'i'orneyg,

Se t. 4, 1962 H. FRANKMANN 3,052,745

SECONDARY ELECTRIC BATTERIES Filed Sept. 21, 1959 2 Sheets-Sheet 2 Imremor Hans FranKmann Unite States 3,952,745. Patented Sept; 4, 1962 Fice 3,052,745 SECONDARY ELECTRIC BATTES Hans Franlnnann, 3 Galway Grove, Greenhill, Wigan, Lancashire, England Filed Sept. 21, 1959, Ser. No. 841,136 Claims priority, application Great Britain Oct. 29, 1958 5 Claims. (Cl. 136-162) This invention relates to secondary electric batteries and is particularly, though not exclusively, applicable to such batteries or accumulators, as they are called, as fitted to mechanically propelled vehicles for the ignition and/ or lighting system thereof in combination with a dynamo driven from the engine of the vehicle.

One of the main problems with such accumulators is the attention necessary to maintain the correct level of the acid or other dielectric by topping up with distilled water to replace loss by evaporation. The need for such topping up varies with each vehicle, as Well as conditions of use, and depends largely on the rate of charge and the amount of current used. The main loss through evaporation occurs through overcharging, that is to say, from continuation of charging after the fully charged state has been reached. Lack of frequent checking of level can cause damage by allowing the level to fall below that of the top of the plates, whilst ineflicient servicing can still leave the top of the plates uncovered, or alternatively, can result in overfilling. The latter can give rise to loss of the di-electric which will result in damage to terminals or to any part with which it comes into contact.

The object of the present invention is a simple means for ensuring that the level of the electrolyte in each of the cells is properly and automatically maintained at the correct level at all times.

According to the invention, each cell is fitted with a float-controlled inlet valve arranged to control the admission of make-up water from a reservoir.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 shows in side view and partly in section, an accumulator having automatic liquid level adjustment means.

FIG. 2 shows the sectioned part of FIG. 1 to a larger scale, and,

FIG. 3 shows an alternative embodiment.

Referring now to FIGS. 1 and 2 of the drawings, a float-controlled inlet valve arrangement to allow for the automatic adjustment of liquid level in an accumulator 11 includes a needle valve assembly 12 disposed within and beneath a stopper 13.

The valve assembly 12 includes a needle 12a mounted for vertical reciprocating motion axially of the bore hole 14 in a valve carrying stem 15, said bore hole 14 comprising an upper part 14a and a lower, wider portion 14b in which said needle 12a moves. The upper pointed end of the needle 12a may extend into the upper part 14a of the bore hole 14 partially to obstruct the same and thus control the rate of flow therethrough. The needle 12a is adapted for retention within the lower part of the bore hole 14 and allowed a limited movement longitudinally thereof by means of a grub screw extending from the side of the bore hole and engaging an elongated recess in the side of the needle. Such retention means is not shown in the drawings. A radially-directed through hole 16 is provided in the wall of valve-carrying stem 15, said hole 16 being located adjacent the neck between the two parts 14a, 14b of the bore hole and in the wider portion thereof. Said through hole 16 is in direct communication with the interior of the accumulator 11.

In the lower end of the needle 12a is rigidly secured a flat float 12!), said float being of such material as will be inactive to the effects of the liquids with which it will normally come into contact. An eminently suitable material has been found to be hard cellular plastic.

The valve-carrying stem 15 is mounted Within the stopper 13, said stopper 13 being adapted for screw-threaded attachment to the top 11a of the accumulator 11. Gas vents 13a are provided in the stopper 13.

In the top of the bore hole 14 is connected a water feed line 17, said feed line terminating at a filler cap 18. The filler 18 is provided with a cap 18a and serves as a reservoir for distilled water.

In use, so long as the level of electrolyte in the accumulator remains at the requisite level, flow of distilled water from the reservoir to the accumulator will be prevented by the needle 12a of the valve assembly 12 extending into and blocking the upper part 14a of the bore 14.

Upon a fall in electrolyte surface level, the float 12b will be lowered and the needle 12a at least partially removed from the upper part 14a of the bore 14. Thus, distilled water may flow from the reservoir into the accumulator.

When the electrolyte again reaches the requisite level the needle valve will close.

It has been found convenient to provide a common feed line for a plurality of accumulators, the capacity of the reservoir being such as to hold a given supply for said plurality.

In an alternative embodiment, see FIG. 3, a valve chamber 21 for an inlet ball valve assembly 22 is formed in the filler plug 23 with outlet passages 24a, 24b leading from the upper end of the said chamber 21 to the lower end of the filler plug 23. Centrally of the plug 23 and leading into the valve chamber 21 is a guide hole 25 for a heading valve-operating stem 26, the head of which 26a is adapted to raise the valve ball 27 onto a seating 28 formed in the upper end of the valve chamber 21. A tube 29 is located in the top of the plug 23, leading to the valve chamber through the seating, and adapted at its upper end 2911 to receive a flexible connecting. tube 30 of suitable material, such as transparent plastic.

Complementary with such modified filler plug is a flat float (not shown) which may conveniently be made of hard cellular plastic, which float is adapted to engage the valve-operating stem to hold the valve ball against its seating when the electrolyte in the cell is at the correct level.

A multi-celled reservoir to hold distilled water may be provided, said reservoir being mounted above the level of the accumulator and having the flexible tubes from each of the accumulator cells connected thereto.

By means of automatic replenishing means constructed in accordance with the present invention, periodic inspection or servicing will suffice, the time between successive servicings being dependent upon the capacity of the reservoir and the number of cells supplied thereby.

"In a further embodiment of the present invention the valve operating stem 26 (FIG. 3) is secured to the float. the latter being of such dimensions as to be capable of being removed from the top 11s: of the accumulator 11 upon removal of the filler plug 23 therefrom. In the further embodiment the float is cylindrical, of an outer diameter of seven-eighths of an inch and five-eighths of an inch deep. The float is secured to the lower end of the stem 26, the flange at the upper end of said stem 26 being removably secured thereto by screw threaded means.

In some arrangements the reservoir will be provided with outlet valve means, such means being manually operated to permit the passage of make-u water from the reservoir to the accumulator feed pipes and thence, as required to the accumulator cells.

The reservoir may be in the form of a funnel as shown 3 in the drawings, or alternatively, in the form of a header tank.

It will be evident from the foregoing that the flow of water from the supply means to the supply side of the valve arrangement on the battery may be automatic, as in the case when no outlet valve means is provided on the water supply means, or controlled, as when outlet valve means are provided.

I claim:

1. In a multi-cell storage battery having a filling opening in the top of each cell, a plug adapted to fit into said cell, an integral externally threaded depending extension on said plug, a valve chamber in the upper end of said extension, a through passage in the upper portion of said plug for connection to a source of topping-up water and communicating with said chamber, said extension having a guide hole at its lower end communicating with said chamber, a float-operated stem slidably located in said guide hole, said float being below said extension and attached to the lower end of said stem, the upper end of said stem terminating in said chamber, a ball valve in said chamber and remote from said float and resting on said upper end and adapted to contact the lower end of said through passage to close the same, said extension having at least one outlet passage separate from said guide hole and extending from the lower portion of said extension to communicate with said chamber and said through passage, said extension being above the normal liquid level of said cell.

2. Means for supplying topping-up water to the cells of a multi-cell secondary electric battery according to claim 1 outlet characterized in that said further passage is horizontally directed at least where it connects with the valve chamber.

3. Means for supplying topping-up water to the cells of a multi-cell secondary electric battery according to claim 1 outlet characterized in that said further passage has a part thereof parallel to the first passage where it communicates with the interior of the cell.

4. Means for supplying topping-up water to the cells of a multi-cell secondary electric battery according to claim 1 further characterized in that the diameter of said valve is less than that of said through passage.

5. Means for supplying topping-up water to the cells of multi-cell secondary electric battery according to claim 1 further characterized in that said stem has a head the diameter of which is less than that of the upper part of said through passage but greater than the diameter of said guide hole in which said stern operates.

References Cited in the file of this patent UNITED STATES PATENTS 1,354,800 Butler Oct. 5, 1920 1,361,437 Blau Dec. 7, 1920 1,421,582 Seng July 4, 1922 1,469,963 Sartakofi Oct. 9, 1923 1,580,493 Johnson Apr. 13, 1926 2,104,672 Rainer Jan. 4, 1938 2,143,340 Willits Jan. 10, 1939 2,161,776 Orr June 6, 1939 2,756,769 Martin et a1. July 31, 1956 

